Weather Journal: Heavy Rain Showers on Tap for Leap Day

Rain, and lots of it, may be heading toward the New York region for Wednesday.

Rain by the bucketful will afflict much of Greater New York on Wednesday, as accumulating snow is a possibility for points on the northern fringes of the metro area.

At times, heavy showers on this Leap Day may feel like four years’ worth of rain all at once (not really, but still). In northern parts of the city and environs (like the Bronx and Westchester), the moisture will briefly manifest itself in the form of snowfall, but shift over to all rain by lunchtime.

For the Hudson Valley (ex-Rockland and Westchester), a winter weather advisory has been issued to warn of incoming snow accumulation. The rain/snow line looks to set up somewhere from northern New Jersey to northern Westchester County, N.Y., to north of about 10-15 miles inland of coastal Connecticut.

Long Island and the majority of New Jersey and New York City will have a completely rain event. Should the cold air associated with this system prove stronger than currently forecasted, some of that snowfall could spread sothward into the city.

The Weather Service’s latest map of forecasted totals shows a dusting in Rockland and Westchester Counties, increasing to a maximum of about five inches around Albany. Once again, there’s about a two-thirds chance that New York City sees nary a flake from this storm.

This forecast comes courtesy of a rare weather pattern (at least this winter): a high pressure system over Atlantic Canada that has been noticeably absent lately will funnel cold air southward from Greenland and the Arctic and trap it against the relatively higher elevations of the Catskills and the onshore flow generated by the coastal storm system coming up the mid-Atlantic coast.

As a result, the latest models have flip-flopped back to this being a relatively favorable environment for snowfall in upstate New York, at least during initial hours of the storm.

Tweet your snow observations and pictures to @WSJweather, as we attempt to crowd-source what is surely one of the last winter weather events of the season.